Struts2学习笔记(3) - 自定义截拦器

1.编写自定义截拦器类
AuthenticationIntecepter.java
此截拦器用于验证用户是否已经登录,若未登录,跳转到登陆页面

import java.util.*;
import com.opensymphony.xwork2.*;
import com.opensymphony.xwork2.interceptor.*;

public class AuthenticationInterceptor implments Interceptor {
  public void init();
  public void destroy();
  
  //intercept()方法用于验证用户是否已经登录
  public String intercept(ActionInvocation actionInvocation) throws Exception {
    Map session = actionInvocation.getInvocationContext().getSession();
    User persistUser = (User)session.get(UserKey.userKey);

    if (persistUser = null) {
      return Action.Login;
    } else {
      System.out.println("User Logined");
      return actionInvocation.invoke();
    }
  }
}

2.在struts.xml中配置截拦器

...

<package ... >

  <!-- 声明自定义截拦器和自定义截拦器栈 -->
  <interceptors>
    <interceptor name="authenticationInterceptor" class="com.vea.AuthenticationInterceptor" />

    <interceptor-stack name="myStack">
      <interceptor-ref name="authenticationInterceptor" />
      <interceptor-ref name="defaultStack" />
    </interceptor-stack>
  </interceptors>

  <!-- 声明包的默认截拦器栈 -->
  <default-interceptor-ref name="myStack" />

  <!-- 声明结果和结果操作 -->
  <global-results>
    <result name="login" type="redirect">/LoginForm.action</result>
    <result name="error">/Error.jsp</result>
  </global-results>

  <!-- 声明异常类型及其映射名称 -->
  <global-exception-mapping>
    <exception-mapping exception="java.lang.Exception" result="error" />
  </global-exception-mapping>

...